The 2010 Buick LaCrosse sedan made its debut a year ago, and it's been a huge hit. Kelsey Mays reviewed the whole LaCrosse lineup last year, including CX and CXL trims with the 3.0-liter V-6, and the top CXS trim level with the 3.6-liter V-6. Now, Buick has added a four-cylinder version of the CX to lower the price a bit and boost gas mileage. (See all versions compared.) All these cars are 2010 models, so Kelsey's review remains a comprehensive evaluation. I'll concentrate on the new four-cylinder's performance and some new observations.

Overall, the four-cylinder LaCrosse will further expand the model's considerable appeal, but its modest power means it's unlikely to become a significant part of the mix.

In terms of base price, the four-cylinder saves you only $840 over the V-6-powered CX, but the mileage bump is a more significant 2 mpg in the city (to 19 mpg), 4 mpg on the highway (to 30 mpg) and a combined 2 mpg improvement in mixed driving (to 23 mpg).

• Modest Power, at Best
• The Comfort Story
• Rolling Ding Factory
• Safety
• LaCrosse Four-Cylinder in the Market